(CNN) – The campaign for Tommy Thompson said the Senate hopeful's son apologized Monday after making a comment referencing President Barack Obama's birthplace at a campaign event.

Jason Thompson, whose father is running as the GOP nominee in a tight contest in Wisconsin, said it was time to send President Barack Obama "back to" Kenya.

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Thompson cited Romney's campaign as being partly to blame for his slipping poll numbers. His comments come after a Marquette University Law School poll released Wednesday showed Thompson trailing Democratic opponent Tammy Baldwin by nine points among likely voters in the Senate race. The same poll showed Thompson leading Baldwin by nine points one month earlier.FULL POST

(CNN) - A new poll of Wisconsin likely voters released Wednesday afternoon shows President Barack Obama with a double digit lead over Republican presidential candidate Mitt Romney there. It stands in contrast to other national and state polls released Tuesday and Wednesday which have shown a close race, some giving Obama a slight advantage over Romney.

The Marquette Law School Poll put Obama 14 percentage points ahead of Romney among likely voters in the Badger State. It also shows a significant change in the Wisconsin race for a U.S. Senate seat.FULL POST

(CNN) - New polls released Thursday indicate three competitive Senate races remain tight in Ohio, Wisconsin and Florida, according to surveys by Quinnipiac University, CBS News, and The New York Times.

(CNN) – Wisconsin's Senate GOP battle is shaping up to end in a close finish Tuesday as voters cast their ballots for the competitive four-way race.

Heading into the contest, a recent poll shows former Wisconsin Gov. Tommy Thompson as the frontrunner in the crowded field of candidates, with businessman Eric Hovde, former Rep. Mark Neumann and state assembly speaker Jeff Fitzgerald following behind.FULL POST

(CNN) – Three months ahead of November's general election, races for the U.S. Senate are deadlocked in Virginia and Wisconsin, according to a poll released Wednesday.

Virginia's two candidates – former Governors Tim Kaine and George Allen – are statistically tied in their race to replace retiring Democratic Sen. Jim Webb. Kaine, a Democrat, stood at 48% in the Quinnipiac University/CBS News/New York Times poll, while Allen, a Republican, was at 46%.FULL POST